Circuit Reliability Improvement By Detecting and Mitigating High Voltage Transient Event At Supply

Abstract

A circuit reliability system with a first voltage supply for outputting a first voltage and a second voltage supply for outputting a second voltage. The system also includes: (i) at least one node for providing a potential in response to the first voltage and the second voltage; (ii) monitoring circuitry for detecting the first voltage exceeding a threshold; and (iii) disabling circuitry, for disabling the second voltage supply in response to the monitoring circuitry detecting the first voltage exceeding a threshold.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001]This application claims priority to, the benefit of the filing date of, and hereby incorporates herein by reference, U.S. Provisional Patent Application 62 / 199,705, entitled “Mitigation of Device Reliability Concern By Detecting High Voltage Transient Event At Supply,” filed Jul. 31, 2015.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]Not Applicable.BACKGROUND OF THE INVENTION[0003]The preferred embodiments relate to electrical systems and methods and, more particularly, to improving circuit reliability by detecting and mitigating high voltage transient events at the circuit voltage supply.[0004]During fast transient conduction in a passenger vehicle fitted with a 12V or 24V electric system, supply lines could have a spiking transient emission because of the inductance on electric wires. This voltage spikes could go up to 55V on top of the supply voltage. Therefore, the supply voltage total can spike up to 13V (typi...

AI Technical Summary

Benefits of technology

The patent describes a system that prevents damage to electronic circuits. It includes two voltage supplies, a monitoring circuit for detecting the first voltage, and a disabling circuit for disabling the second voltage supply if the first voltage exceeds a certain level. The technical effect of this system is to prevent damage to electronic circuits caused by overvoltage.

Problems solved by technology

Excessive voltages from the combination of transients and a charge pump pose risk to other circuit structures and elements.

A potential compromise, therefore, is to limit the charge pump output voltage to reduce the chance of breakdown, but such a limitation would likewise limit the turn-on resistance of the switch, too.

An increase in the protection of such devices, however, requires a corresponding increase in size and spacing, and, as a result, overall chip area would be significantly, and undesirably, increased.

In some manufacturing processes, however, such devices have isolated PN-junction ratings below or barely at these levels, so such options may be limited or even the most robust of the devices may still have questionable chances of surviving the peak voltages at, or slightly exceeding, its limit.

Given the preceding discussion, certain applications will have requirements that are not sufficiently addressed by the prior art.

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